JPH0528231B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Background) The present invention relates to a novel method for producing epoxy compounds. Epoxy resin is an industrial material that has many uses such as adhesives, molding agents, sealants, and paints.Epoxy resin is an industrial material that has many uses such as adhesives, molding agents, sealants, and paints. Among them, the so-called EP-vis type and novolak type, which are manufactured from compounds with phenolic hydroxyl groups and epihalohydrin, are used as raw materials. occupies the majority.

(Prior Art and Its Disadvantages) However, in a production method in which a compound having a phenolic hydroxyl group and epihalohydrin are reacted in the presence of an alkaline substance to convert the phenolic hydroxyl group into glycidyl ether, the product resin contains epihalohydrin. The halogen atoms derived from are chemically bonded to the resin itself,
It has become clear that contamination as impurities is unavoidable.

Among the uses of epoxy resins, especially when used in electronic materials, it is said that halogen impurities are released as hydrogen halides due to moisture etc. during long-term use, leading to corrosion of metal materials. ,
There is an urgent need to resolve this issue.

In addition, a method for producing an epoxy compound by reacting an unsaturated compound with a peroxide without using epihalohydrin is also known, and products are actually on the market. A typical epoxy resin obtained by this method is alicyclic epoxy resin, but it has the disadvantage that curing with common curing agents such as amine compounds and phenol novolak compounds is slower than with glycidyl ether type epoxy resins. Although they do not contain halogens, their uses are limited, and they have not yet been replaced by epoxy compounds produced by the epihalohydrin method.

On the other hand, a method of decomposing and decarboxylating a carbonate compound is known as one method for producing an epoxy compound without using epihalohydrin or peroxide. However, the conventional technology is a method for obtaining monofunctional low molecular weight epoxy compounds such as propylene oxide and glycidol (for example, JP-A-57-144272,
144271, U.S. Patent No. 2856413, etc.), and there were restrictions on the carbonate that could be selected as a starting material, making it difficult to say that it had versatility.

The present inventors focused on the fact that the method of producing an epoxy compound via carbonate essentially does not contain halogens such as chlorine, and conducted extensive studies to establish a versatile production method that uses a carbonate compound as an intermediate. As a result, we have arrived at the present invention.

(Structure of the present invention) That is, the present invention provides a method for producing an epoxy compound, which comprises converting the hydroxyl group of a compound having a phenolic hydroxyl group into 1,2-carbonated glycerin ether, and then converting it into glycidyl ether. ”.

In the present invention, monohydric phenol compounds and polyhydric phenol compounds can be used as the compound having a phenolic hydroxyl group.

As a monovalent phenol compound, phenol, o
-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, p-xylenol Examples include enylphenol, t-butylphenol, p-nonylphenol, p-vinylphenol, α-naphthol, β-naphthol, and the like.

Polyphenol compounds include monocyclic polyphenols such as catechol, resorcinol, hydroquinone, dihydroxytoluene, naphthalene diol, t-butylcatechol, t-butylhydroquinone, pyrogallol, and phloroglucinol; bisphenol A, and bisphenol A; Phenol F, bisphenol S, 4,4'-dihydroxybenzophenone, 4,4'-dihydroxydiphenyl ether, phenolphthalein, phenol novolac resin, o-cresol novolac resin, poly-
p-hydroxystyrene, phenol-glyoxal condensate, resorcinol-formalin condensate, 2,2'-biphenyldiol, 1,1'-bi-
Examples include compounds in which multiple phenol skeletons are linked by chemical bonds, such as 2-naphthol.

The monovalent and polyvalent phenol compounds described herein include functional groups containing halogen, oxygen, nitrogen, and sulfur on the phenol ring or on the hydrocarbon skeleton substituted on the phenol ring, such as halogen groups, ether groups, ester groups, and carbonyl groups. , carboxylic acid group,
It also includes those having a hydroxyl group, an aldehyde group, an amino group, an amide group, a nitrile group, a nitro group, a thiol group, a thioether group, and other heteroaromatic groups such as a pyridyl group and an imidazole group.

A compound having a phenolic hydroxyl group, 1,2
- There are the following two methods for converting into carbonated glycerin ether.

The first method is a method in which glycidyl alkyl carbonate is reacted with a phenolic compound, and 1,2-carbonated glycerin ether of phenols can be obtained in high yield.

Examples of the glycidyl alkyl carbonate include glycidyl methyl carbonate, glycidyl ethyl carbonate, glycidyl-i-propyl carbonate, glycidyl-n-propyl carbonate,
Glycidyl butyl carbonate and the like can be used.

Glycidyl alkyl carbonate can be produced by transesterification of dialkyl carbonate and glycidol, or by replacing chlorine of phosgene with alcohol and glycidol sequentially or simultaneously.

Although the reaction between glycidyl alkyl carbonate and a compound having a phenolic hydroxyl group can be carried out without a catalyst, it is possible to react with a tertiary amine, a quaternary ammonium compound,
Metal hydroxides, metal alkoxides, metal halides, metal carbonates, metal bicarbonates, metal sulfates,
When a catalyst such as a metal nitrate is used, the progress of the reaction is accelerated and production can be performed in a shorter time. As a catalyst, triethylamine, tetramethylammonium chloride, tetrabutylammonium bromide, caustic soda, caustic potash, sodium methoxide, potassium iodide, sodium iodide, potassium chloride, sodium chloride, sodium carbonate, sodium hydrogen carbonate, sulfuric acid. Examples include sodium, potassium sulfate, sodium nitrate, potassium nitrate, etc.

The amount of catalyst is 0.01 to 10% based on the starting material, and is added to the reaction system depending on the activity of the catalyst.

The reaction temperature ranges from 0 to 0 depending on the reactivity of the reaction raw materials.
200℃ is appropriate.

Generally, below 0°C, this reaction is slow, and above 200°C, side reactions such as decomposition of carbonate groups increase, which is not preferable.

Since the produced carbonate undergoes transesterification with the by-product alcohol and changes into 1,2-diol, it is preferable to carry out the reaction while removing the by-product alcohol.

Removal of the by-product alcohol can be carried out by reducing the pressure of the reaction system to the pressure necessary for distilling off the alcohol, depending on the reaction temperature. Alternatively, means such as azeotropy may be used. When the raw materials or products are solid or highly viscous, the reaction can be carried out by adding an appropriate amount of solvent to the reaction system, if necessary. At this time, the solvent must have a boiling point higher than that of the by-product alcohol and must not react with glycidyl groups, carbonate groups, or other functional groups in the raw materials.

That is, usable solvents include dioxane,
Ethers such as isopropyl ether, butyl ether and anisole, aromatic hydrocarbons such as benzene, toluene and xylene, halogenated hydrocarbons such as carbon tetrachloride and trichlene, aliphatic hydrocarbons such as octane and decane, methyl isobutyl Other examples include ketones such as ketone, diethyl ketone, and cyclohexanone, as well as dimethyl sulfoxide, dimethylformamide, and γ-pyrodrine. Furthermore, since esters such as ethyl acetate and butyl acetate usually undergo some transesterification, they may not be of practical use depending on the amount of transesterification under the reaction conditions. Alcohols such as methanol, ethanol, n-propanol, and i-propanol tend to react easily with glycidyl groups, and for the same reason as esters, they are often not practically usable.

Compounds with phenolic hydroxyl groups are 1,2-
The second method for converting into carbonated glycerin ether is to add a phenolic compound and glycidol to form a glycerin ether of a phenolic compound, and then transesterify the diol with a dialkyl carbonate, or add phosgene or the like to the diol. This is a method of reacting to form glycerin carbonate.

The reaction between phenolic hydroxyl groups and glycidol proceeds even without a catalyst, but by using a catalyst,
It is possible to increase the reaction rate and also increase the selectivity of the addition reaction of glycidol to the terminal carbon. Examples of catalysts include compounds such as tertiary amines, quaternary ammonium compounds, metal hydroxides, metal alkoxides, metal halides, metal carbonates, metal bicarbonates, metal sulfates, and metal nitrates. , triethylamine, tetramethylammonium chloride, tetrabutylammonium bromide, caustic soda, caustic potash, sodium methoxide, potassium iodide, sodium iodide,
Examples include potassium chloride, sodium chloride, sodium carbonate, sodium hydrogen carbonate, sodium sulfate, potassium sulfate, sodium nitrate, potassium nitrate, and the like.

The amount of catalyst is added to the reaction system in an amount of 0.01 to 10% based on the starting material depending on the activity of the catalyst.

The reaction between glycidol and a compound having a phenolic hydroxyl group is carried out at 10-150°C. Below 10°C, the reaction is slow, and above 150°C, polymerization of glycidol increases, which is not preferable.

In the reaction, it is preferable to drop glycidol to the phenol compound in terms of suppressing the reaction heat and preventing polymerization of glycidol, but if the conditions are mild, a method in which all the raw materials are added to the reactor from the beginning may be used. A solvent can also be used if necessary.

Purification operations such as distillation of low-boiling components and washing with water are performed as necessary from the reaction crude liquid to extract a glycerin ether compound, which is used as a raw material for carbonation.

Carbonation can be carried out by transesterification of a dialkyl carbonate and glycerin ether or by reaction of phosgene or the like with a diol. Examples of dialkyl carbonates that can be used include dimethyl carbonate, diethyl carbonate, di-i-propyl carbonate, di-n-propyl carbonate, dibutyl carbonate, and the like.

In carbonate exchange, the reaction can be promoted by using a catalyst. Examples of catalysts that can be used include alkali metal hydroxides, alkali metal alkoxides, alkali metal halides, alkali metal organic carboxylic acids, and alkali metal salts of nitric acid.

The reaction temperature for the exchange reaction can be selected depending on the reactivity of the carbonate and the amount and type of catalyst used. Further, at this time, in order to promote the reaction, it is preferable to carry out the reaction while distilling off the alcohol derived from the dialkyl carbonate. A solvent may be used if necessary.

When using phosgene, carbonation can be achieved by dehydrochlorination alone or together with a deoxidizing agent.

The carbonate compound obtained by either method is purified to a purity suitable for the next decomposition step by a purification method such as washing with water or removing a low boiling point, if necessary.

The carbonate compound is converted into an epoxy resin by a decarboxylation reaction by thermal decomposition after being purified or unpurified.

Preferred reaction conditions are 150-300 ℃ under normal pressure or reduced pressure.
℃, and the reaction proceeds even without a catalyst, but the use of a catalyst can increase the yield of epoxy groups. As such a catalyst, an alkali metal halide provides a high yield, but the catalyst is not limited to an alkali halide, and other compounds may be used. Also, multi-component catalyst systems may be used.

The produced epoxy resin is subjected to a purification operation as necessary. For example, when an alkali halide is used as a catalyst, the catalyst can be removed by washing with water.

(Effects of the present invention) The epoxy resin obtained by the method of the present invention does not contain halogen as an impurity, does not corrode metals, has a fast curing speed, and is versatile. Raw materials can be selected, and it is particularly suitable for encapsulating integrated circuits.

EXAMPLES The present invention will be explained in more detail with reference to Examples below.

Example 1 360 g (4 moles) of dimethyl carbonate, 148 g (2 moles) of glycidol, and 0.50 g of potassium chloride as a catalyst were charged into a reactor equipped with a 10-stage Olderschau column, and a reaction was carried out under reflux. When methanol began to be produced as a by-product, it was distilled off from the top of the column and removed from the reaction system, and the reaction was continued until no more methanol was distilled out. After the reaction crude liquid was flash-distilled to remove the catalyst, the distillate of the flash-distillation was rectified in a 10-stage Olderschau column.
Glycidyl methyl carbonate (hereinafter abbreviated as GMC) with a purity of 98.7% (by gas chromatography) was obtained as a 140-150° Hg fraction.

145 g of the obtained GMC was mixed with 114 g of bisphenol A.
(OH equivalent: 114) was charged into a reactor equipped with a stirrer together with 2.6 g of dimethylbenzylamine, and the reaction was carried out under a reduced pressure of 100 mmHg while maintaining the internal temperature at 100°C until no by-product methanol was distilled out. Ta.

Next, the reaction crude liquid was transferred to a simple distillation apparatus equipped with a capillary, and the temperature of the reactor was raised to 150° under a reduced pressure of 1 mmHg to remove low boiling points.

The reaction product was analyzed by gas chromatography internal standard method, and after confirming that there were only trace amounts of low-boiling components such as GMC, methanol, and glycidol, IR spectrum analysis was performed. Since strong absorption of carbonate bonds was observed at 1800 cm ^-1 , it was confirmed that the reaction product was 1,2-carbonated glycerin ether of bisphenol A.

100 g of the obtained 1,2-carbonated glycerin ether of bisphenol A was charged together with 2 g of potassium iodide into a reaction device capable of reducing the pressure.
The system was evacuated to 20 mmHg and heated to 200°C using an oil bath.

Heating was continued until foaming due to decarboxylation of the carbonate compound was no longer observed.

The product was a viscous liquid, which was dissolved in methyl isobutyl ketone, the catalyst was removed by washing with water, and then the solvent was removed.

The oxirane oxygen content of the purified resin was measured and found to be 5.8%. In addition, when residual iodine was analyzed by the bomb combustion method, it was analyzed to be 9 ppm, and the halogen content of the epoxy resin corresponding to this example by the epichlorohydrin method is several hundred ppm even if it is a high-purity product. It was confirmed that the method is suitable for producing epoxy resins with low halogen impurities.

Example 2 132g (1 mol) of GMC was added to bisphenol F100.
(manufactured by Dainippon Ink Co., Ltd., OH equivalent: 100) and 2.3 g of potassium iodide were charged into a reactor equipped with a stirrer, and the internal temperature was maintained at 100°C at 100 mmHg.
The reaction was carried out under reduced pressure until no by-product methanol was observed to be distilled out.

The pressure was further lowered to 1 mmHg to remove low-boiling components. The reaction products were analyzed by gas chromatography internal standard method, and GMC, methanol,
After confirming that there were traces of low-boiling components such as glycidol, IR spectrum analysis was performed. 1800
Since strong absorption of carbonate bonds is observed in cm ^-1 , the reaction product is 1,2 of bisphenol F.
- It was confirmed that it was carbonated glycerin ether. In addition, absorption of OH groups is observed at 3400 cm ^-1 and the amount of product obtained by reducing the catalyst weight is
Since the amount was 184 g, it was found that the yield of the etherification reaction was 84% based on the total OH.

Calculation formula (184-100) / 100 x 100 = 84%...Increased weight...Increased weight when 100% carbonated was heated to 200°C.

Heating was continued until foaming due to decarboxylation of the carbonate compound was no longer observed.

The product was dissolved in methyl isobutyl ketone, potassium iodide was removed by washing with water, and then the solvent was removed.

The oxirane oxygen content of the product was 5.2%, and the residual iodine by bomb combustion method was 7 ppm.

Example 3 Phenol 188g (2 mol), GMC 290.4g (2.2
Charge 4.8 g of sodium hydrogen carbonate (mol) into a reactor equipped with a stirrer, reduce the pressure of the system to 100 mmHg,
The reaction was carried out at 100°C. While by-product methanol was distilled out and removed, the reaction was continued until methanol generation was no longer observed.

Acetone was added to the crude liquid to form a solution, heated to remove sodium hydrogen carbonate, and then cooled to precipitate crystals. This crystal has 1800 in the infrared spectrum
The fact that there is an absorption by the CO group of carbonate at cm ^-1 and the nmr spectrum shows that 1,
It was confirmed that it was 2-carbonated glycerin ether.

Carbonate compound 19.9g, potassium iodide
0.4 g was charged into a reactor, and the reactor was heated to 200° C. under a reduced pressure of 20 mmHg, and the reaction was carried out while distilling the generated phenyl glycidyl ether until almost no distillate was generated.

The distillate is 9.8g, and the phenyl glycidyl ether content is 93.7% by gas chromatography.
It was hot.

This distillate was produced using the cylinder combustion method, and the iodine content was
It was confirmed that the epoxy resin material contained only 5ppm of halogen impurities.

Claims (1)

[Claims] 1. A method for producing an epoxy compound, which comprises converting the hydroxyl group of a compound having a phenolic hydroxyl group into 1,2-carbonated glycerin ether, and then converting it into glycidyl ether.